Self-cleaning ovens which are incorporated into self-standing ranges are well known. Such ovens conventionally have an oven door which is hingedly secured to a range body. The oven door may be opened to gain access to an oven cavity. The oven door may also be closed to close the opening for cooking objects placed in the cavity or cleaning the cavity. One or more heating elements reside in the oven cavity for cooking purposes.
Motorized latches which are used to lock oven doors in a closed position so that the oven cavity may be self cleaned are well known.
Assignee's U.S. Pat. Nos. 6,302,098 and 6,698,418 each disclose a motorized oven door latch assembly for locking an oven door in a locked and sealed position for purposes of cleaning the oven. Such oven door latches are activated by a rotary motor located remotely from the latch member above the oven cavity. Activation of the motor causes a rod to translate which causes a latch member secured to the front of the rod to engage the oven door so that the oven door may not be opened. After the cleaning has occurred, the motor is reactivated, causing the latch member at the front of the rod to disengage the oven door so that the oven door may be opened.
Each of these motorized oven door latch assemblies utilizes a spring mechanism to bias the latch member into engagement with the oven door. The spring is typically secured at one end to a mounting plate secured to the range and is secured at the other end to the movable latch member. With repeated use, the spring may wear down and may eventually fail to function properly if subject to enough use.
Motorized range lock assemblies such as the one disclosed in U.S. Pat. No. 6,315,336 have been manufactured and sold without such a spring. One disadvantage with motorized oven door latch assemblies having no spring is that the latch member moves between two positions rather than three. In other words, existing range lock assemblies without springs do not provide what is known in the industry as a “pull in” feature. The pull in feature enables the oven door to move to a locked and sealed position when the latch member is in its third position. When the latch member is in this third pulled in position, the motorized range lock assembly causes the oven door to exert pressure on a gasket sandwiched between the front wall of the range and the oven door.
Therefore, a need exists for a motorized oven door latch assembly which provides the pull in feature without the use of a spring.